from kivy.uix.floatlayout import FloatLayout
from kivy.uix.button import Button

class freefall_layout( FloatLayout ):
    def __init__( self, **kwargs ):
        super( freefall_layout, self ).__init__( **kwargs )
        self.add_widget( Button( text = 'test free fall', 
            pos_hint = { 'x' : 0.0, 'y' : 0.0 },
            size_hint = ( 1.0, 1.0 ) ) )
    
if __name__ == '__main__':
    from kivy.app import App
    class testApp( App ):
        def build( self ):
            return freefall_layout()
    testApp().run()